While Image Links are live embedded versions of your wireframes, you can instead choose to attach a static version of your wireframes.
Whether you go with Balsamiq for Desktop, our standalone desktop app, or one of our subscription-based versions, every single one of them allows you to export your wireframes to PDF or PNG. You can then attach the exported PDF or PNG to a Confluence page or Jira issue, and your wireframes will display like any other image or PDF.
Keep in mind that the actual wireframing will still happen outside of Atlassian, and continued iterations of the wireframes would need to be exported and attached again.
We are happy to offer 30-day free trials on all versions, so feel free to take them all for a spin.
Learn how to export your wireframes here: Exporting.